The present invention relates to bags. More specifically, the present invention relates to self-opening style or self-opening square bags, referred to in the industry as SOS bags. This type of bag has a folded rectangular bottom, and is typically used for grocery sacks, lunch sacks, microwave popcorn sacks and other bags which are required to stand on their own when opened. Such SOS bags are disclosed in U.S. Pat. Nos. 3,342,402; 3,606,822; 3,669,347; and 4,490,131.
Tubular sacks with gussetted sides are known. Because the bottom of such a bag is folded, the interior of the bag has folded-over flaps. Unfortunately, small-objects within the bag can become trapped under the flaps, making them difficult to retrieve.
It is known to apply an adhesive to a tubular bag to form and secure the rectangular bottom. However, the adhesive in prior art bags has not been optimally placed so that the bottom flaps are adequately secured. Some prior art configurations secure interior flaps by gluing an insert strip over certain flap edges. For example, U.S. Pat. No. 3,734,395 relates to such a bag.
Desirably, a minimal amount of adhesive is used for producing a bag to keep down costs. Therefore, the adhesive is preferably arranged for a maximum sealing effect with a minimal adhesive expense.